摘要:
To rich the category of crystallization accelerator with bisamide structure of poly (L-lactic acid) (PLLA),N,N'-bis(salicyl) decanedioic acid dihydrazide (SS),as a crystallization accelerator for PLLA,was synthesized from decanedioic acid and salicyl hydrazide,and the influence of SS on the non-isothermal crystallization and melting behavior of PLLA was investigated.The non-isothermal crystallization behavior results showed that SS can significantly promote the crystallization of PLLA,in particular,0.5% SS exhibited the best crystallization accelerating effect for PLLA,and 0.5% SS caused the onset crystallization temperature,non-isothermal crystallization peak temperature,and the non-isothermal crystallization enthalpy to increase from 101.4 °C,94.5 °C,and 0.1 J/g to 122.8 °C,119.5 °C,and 32.6 J/g,respectively.In addition,the cooling rate was also very important factor to affect the crystallization behavior of PLLA.However,the effect of the set final melting temperature on the non-isothermal crystallization of PLLA/SS was negligible.The melting behavior of PLLA/SS after isothermal crystallization further confirmed the effect of different SS concentration on the crystallization of PLLA,however,this difference can decrease with an increase of isothermal crystallization time.%为丰富双酰胺类聚L--乳酸结晶促进剂的类别,以癸二酸和水杨酰肼为原料制备具有双酰胺结构的癸二酸二水杨酰肼作为聚L--乳酸的结晶促进剂,研究其对聚L--乳酸的非等温结晶行为和熔融行为的影响.非等温结晶行为显示癸二酸二水杨酰肼可显著提升聚L--酸的结晶能力,尤其是0.5%的癸二酸二水杨酰肼对聚L-乳酸具有最佳的结晶加速效应,可使聚L-乳酸的起始结晶温度、结晶峰温度以及非等温结晶焓分别从101.4°C,94.5°C,0.1 J/g增加到122.8°C,119.5 °C,32.6 J/g,另外,非等温结晶过程中降温速率是影响聚L-乳酸结晶的重要因素,而最终熔融温度对非等温结晶行为的影响较小.等温结晶后的熔融行为研究进一步证实了不同含量癸二酸二水杨酰肼对聚L-乳酸结晶促进作用的贡献大小,但促进作用上的差别会随着等温结晶时间的增加而减小.